Molecular composite of industrial nylon

ABSTRACT

A molecular composite of an industrial nylon includes a nylon having molecular chains and a poly-m-phenyleneisophthalamide (PmIA) polymerized between the molecular chains of the nylon in a copolymerization manner, thereby forming an interblock copolyamide material consisting of the molecules of the nylon and the molecules of the PmIA. Thus, the molecular composite has proper flexible elongation and tensile strength, so that it is available for various industrial products.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a molecular composite of anindustrial nylon, and more particularly to a molecular composite of anindustrial nylon having proper flexible elongation and tensile strength.

[0003] 2. Description of the Related Art

[0004] A conventional nylon-6 (or nylon-66) in accordance with the priorart is a flexible polyamide which has a folding crystalline structureand has excellent elongation property and softness. However, theconventional nylon-6 (or nylon-66) has a smaller stiffness modulus andworse heat-resistant feature, so that it is not available forheat-resistant and wear-resistant industrial products. Takayanagiproposed a research of the nylon-6 and the crystalline wholly rigidKevlar molecule so as to enhance the heat-resistant and wear-resistantfeatures of the nylon-6.

SUMMARY OF THE INVENTION

[0005] The present invention uses a non-crystalline wholly rigidpoly-m-phenyleneisophthalamide (PmIA) to reinforce the flexible nylon-6(or nylon-66).

[0006] The primary objective of the present invention is to provide amolecular composite of an industrial nylon having proper flexibleelongation and tensile strength.

[0007] Another objective of the present invention is to provide amolecular composite of an industrial nylon having an enhancedheat-resistant feature.

[0008] A further objective of the present invention is to provide amolecular composite of an industrial nylon functioning as areinforcement material.

[0009] In accordance with one aspect of the present invention, there isprovided a molecular composite of an industrial nylon, comprising anylon having molecular chains and a poly-m-phenyleneisophthalamide(PmIA) polymerized between the molecular chains of the nylon in acopolymerization manner, thereby forming an interblock copolyamidematerial consisting of the molecules of the nylon and the molecules ofthe PmIA.

[0010] In accordance with another aspect of the present invention, thereis provided a method for manufacturing a molecular composite of anindustrial nylon, comprising the steps of: the nylon-6 prepolymersolution being previously dissolved in the N-methyl-2-pyrrolidone (NMP),then added in the lithium chloride (LiCl) solvent, then reduced to thetemperature of 0° C., then added into the PmIA prepolymer solution to bestirred vigorously, maintained at a relatively lower temperature duringa period of time, increased to the room temperature, stirred during aperiod of time, thereby finishing the reaction, the solution being driedand coated on a clean carrying plate to be heated and dried during a fewhours, then removed outward and placed into an icy water, so that thesalt is diffused, and finally placed into the vacuum oven to be dried,thereby forming the product.

[0011] Further benefits and advantages of the present invention willbecome apparent after a careful reading of the detailed description withappropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a schematic view of a triblock copolyamide in accordancewith the present invention;

[0013]FIG. 2 is a schematic view of a multiblock copolyamide inaccordance with the present invention;

[0014]FIG. 3 is a schematic reaction view of a diamine type nylon-6 inaccordance with the present invention;

[0015]FIG. 4 is a schematic reaction view of a high molecular weightnylon-6 in accordance with the present invention;

[0016]FIG. 5 is a schematic reaction flow chart of the PmIA inaccordance with the present invention;

[0017]FIG. 6 is a schematic reaction flow chart of the triblockcopolyamide in accordance with the present invention;

[0018]FIG. 7 is a schematic reaction flow chart of the multiblockcopolyamide in accordance with the present invention;

[0019]FIG. 8 is a comparison table of the mechanic features between thepolyblend and the pure nylon in accordance with the present invention;

[0020]FIG. 9 is a comparison table of the mechanic features between thecopolyamide and the pure nylon in accordance with the present invention;and

[0021]FIG. 10 is a DSC analysis comparison table of the polyblend, thecopolyamide and the pure nylon in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Referring to FIGS. 1-10, a molecular composite of an industrialnylon in accordance with a preferred embodiment of the present inventioncomprises a nylon-6 (or nylon-66) having molecular chains and apoly-m-phenyleneisophthalamide (PmIA) polymerized between the molecularchains of the nylon-6 (or nylon-66) in a copolymerization manner,thereby forming an interblock copolyamide material consisting of themolecules of the nylon-6 (or nylon-66) and the molecules of the PmIA.

[0023] As shown in FIG. 1, the polymerized pattern of the copolyamide ofthe nylon-6 and the PmIA is nylon-6˜PmIA˜nylon-6, and is the so-calledtriblock polyamide. Alternatively, the polymerized pattern of thecopolyamide of the nylon-66 and the PmIA is nylon-66˜PmIA˜nylon-66.

[0024] As shown in FIG. 2, the polymerized pattern of the copolyamide ofthe nylon-6 and the PmIA is (PmIA˜nylon-6), and is the so-calledmultiblock polyamide. Alternatively, the polymerized pattern of thecopolyamide of the nylon-66and the PmIA is (PmIA˜nylon-66).

[0025] On the other hand, the nylon-6 (or nylon-66) and the PmIA can bemixed in a physically blending manner, thereby forming a polyblend. Inpreparation of the polyblend, the finished nylon-6 (or nylon-66) and thePmIA are dissolved in the formic acid to form an uniform state, thendeposited and cured by a large amount of water, then stationarily placedfor a few days, then washed by the methanol, and then dried in a vacuummanner, thereby forming the polyblend. The made polyblend can be drawnto serve as a knitting material. In addition, the made polyblend can beheat pressed by a heat forming press under the pressure of 20 kg/cm² andthe temperature of 230° C. during 20 minutes, and is naturally cooled tothe temperature of 60° C., thereby forming a sheet plate.

[0026] In the copolyamide material in accordance with the presentinvention, the weight of the PmIA contained in the copolyamide is rangedbetween 5 to 20% so as to provide better mechanic features.

[0027] Referring to FIGS. 6 and 7, in the manufacturing method of themolecular composite of an industrial nylon in accordance with thepreferred embodiment of the present invention, the nylon-6 prepolymersolution is previously dissolved in the N-methyl-2-pyrrolidone (NMP),then added in the lithium chloride (LiCl) solvent, then reduced to thetemperature of 0° C., and then added into the PmIA prepolymer solutionto be stirred vigorously. The system is maintained at a lowertemperature during a period of time, and is naturally increased to theroom temperature, and the stirring action continues a period of time,thereby finishing the reaction. Then, the solution is dried and coatedon a clean carrying plate to be heated and dried during a few hours,then removed outward and placed into the icy water tab, so that the saltis diffused, and finally placed into the vacuum oven to be dried,thereby forming the product.

[0028] Referring to FIG. 5, in the manufacturing method of the PmIAprepolymer solution of the present invention, the m-phenylenediamine(MPA) is dissolved in the NMP, and is added into the LiCl solvent. Thesystem is reduced to the temperature under 0° C. Then, an excessiveisophthaloyl dichloride (IPC) is added, so as to proceed a reaction,thereby forming the PmIA prepolymer solution. In the procedure of themanufacturing method of the PmIA prepolymer of he present invention, theMPA is dissolved in the NMP, and is added into the LiCl solvent. Thesystem is reduced to the temperature of −10 to −15° C. Then, anexcessive IPC is added so as to proceed a reaction at the temperatureunder 0° C. Then, the system is naturally increased to the roomtemperature to continue the reaction. Finally, the system is solidifiedby a large amount of water, washed by the methanol, and is dried undervacuum, thereby forming the PmIA prepolymer.

[0029] In addition, in the manufacturing method of the nylon-6prepolymer of the present invention, the diamine type nylon-6 or highmolecular weight nylon-6 and the coupling agent are reacted andpolymerized with the p-aminophenyl acetic acid (P-APA). The adoptedpolymerization method is the bulk polymerization method. The reaction ofthe diamine type nylon-6 is shown in FIG. 3. The reaction of the highmolecular weight nylon-6 is shown in FIG. 4.

[0030] In preparation of the diamine type nylon-6, nine ε-caprolactamand one ε-aminohexanoic acid in the nitrogen system are reacted during aperiod of time at the temperature of 150° C., then increased to thetemperature of 180° C. to continue to react during a proper period oftime, and then successively increased to the temperature of 200° C.Then, an excessive hex-amethylene diamine (HMDA) is dipped into thesystem and is reacted during a period of time. Finally, the system isincreased to the temperature of 250° C. to continue to react during aperiod of time, then reduced to the room temperature, then mixed withwater to be cured, then circulated during 24 hours with the rate of thewater and methanol equal to 4:1, and is dried under vacuum, therebymaking the diamine type nylon-6.

[0031] In preparation of the high molecular weight nylon-6, nineε-caprolactam and one ε-aminohexanoic acid in the nitrogen system arereacted during 2 hours at the temperature of 150° C., then increased tothe temperature of 250° C. to continue to react during 4 hours, thenreduced to the room temperature, then mixed with water to be cured, thendried under vacuum, then dissolved by the formic acid, then cured by alarge amount of water, then washed by the methanol, and then dried undervacuum, thereby making the high molecular weight nylon-6.

[0032] Thus, the present invention uses the wholly rigid aromatic PmIAto reinforce the nylon-6 (or nylon-66). From the results of the mechanicfeatures, both of the multiblock copolyamide and the physically blendedpolyblend can achieve the reinforcement effect.

[0033] The experiments of the present invention obtain the followingconclusions.

[0034] As shown in FIG. 8, after test, the content of the polyblend ofthe PmIA is increased from 1% to 20% (N_(y) indicates the pure nylon,and M₁ indicates that the content of the polyblend of the PmIA is 1%,etc.), and the tensile strength is increased gradually.

[0035] As shown in FIG. 9, B_(M1) indicates the content of themultiblock copolyamide of the PmIA is 10%, wherein the reinforcementeffect is more outstanding and the tensile strength reaches 78.93MPa. Inthe table, T_(b) is the tensile strength, and M_(i) is the initialmodulus.

[0036] As shown in FIG. 10, the thermal analysis in the DSC indicatesthat the glass transition temperature (T_(g)) of both of the polyblendM₁ to M₅ and the multiblock copolyamide B_(m) is greater than that ofthe single nylon.

[0037] From observation of the surface structure of the scanningelectron microscopy (SEM), the surface structure of the multiblockcopolyamide presents a uniform-phase structure, so that the polymerizedmolecular structure is better.

[0038] Accordingly, the technology of the present invention can enhancethe mechanic features of the molecular composite of the industrialnylon, such as the wear-resistant stiffness, the heat-resistant feature,etc.

[0039] Although the invention has been explained in relation to itspreferred embodiment(s) as mentioned above, it is to be understood thatmany other possible modifications and variations can be made withoutdeparting from the scope of the present invention. It is, therefore,contemplated that the appended claim or claims will cover suchmodifications and variations that fall within the true scope of theinvention.

What is claimed is:
 1. A molecular composite of an industrial nylon,comprising a nylon having molecular chains and apoly-m-phenyleneisophthalamide (PmIA) polymerized between the molecularchains of the nylon in a copolymerization manner, thereby forming aninterblock copolyamide material consisting of the molecules of the nylonand the molecules of the PmIA.
 2. The molecular composite of anindustrial nylon in accordance with claim 1, wherein the nylon isnylon-6.
 3. The molecular composite of an industrial nylon in accordancewith claim 1, wherein the nylon is nylon-66.
 4. The molecular compositeof an industrial nylon in accordance with claim 1, wherein thepolymerized pattern of the copolyamide of the nylon and the PmIA isnylon-6˜PmIA˜nylon-6.
 5. The molecular composite of an industrial nylonin accordance with claim 1, wherein the polymerized pattern of thecopolyamide of the nylon and the PmIA is PmIA˜nylon-6.
 6. The molecularcomposite of an industrial nylon in accordance with claim 1, wherein thepolymerized pattern of the copolyamide of the nylon and the PmIA isnylon-66˜PmIA˜nylon-66.
 7. The molecular composite of an industrialnylon in accordance with claim 1, wherein the polymerized pattern of thecopolyamide of the nylon-66 and the PmIA is PmIA˜nylon-66.
 8. Themolecular composite of an industrial nylon in accordance with claim 1,wherein the molecules of the nylon and the PmIA can be mixed in aphysically blending manner, thereby forming a polyblend.
 9. Themolecular composite of an industrial nylon in accordance with claim 1,wherein the weight of the PmIA contained in the copolyamide is rangedbetween 5 to 20%.
 10. A method for manufacturing a molecular compositeof an industrial nylon, comprising the steps of: the nylon-6 prepolymersolution being previously dissolved in the N-methyl-2-pyrrolidone (NMP),then added in the lithium chloride (LiCl) solvent, then reduced to thetemperature of 0° C., then added into the PmIA prepolymer solution to bestirred vigorously, maintained at a relatively lower temperature duringa period of time, increased to the room temperature, stirred during aperiod of time, thereby finishing the reaction, the solution being driedand coated on a clean carrying plate to be heated and dried during a fewhours, then removed outward and placed into an icy water, so that thesalt is diffused, and finally placed into the vacuum oven to be dried,thereby forming the product.
 11. The method in accordance with claim 10,wherein the PmIA prepolymer solution is made by the steps of: them-phenylenediamine (MPA) is dissolved in the NMP, and is added into theLiCl solvent, the system is reduced to the temperature under 0° C., andan excessive isophthaloyl dichloride (IPC) is added, so as to proceed areaction, thereby forming the PmIA prepolymer solution.
 12. The methodin accordance with claim 11, wherein the PmIA prepolymer is made by thesteps of: the MPA is dissolved in the NMP, added into the LiCl solvent,reduced to the temperature of −10 to −15° C., then an excessive IPC isadded so as to proceed a reaction at the temperature under 0° C., thenthe system is naturally increased to the room temperature to continuethe reaction, then the system is solidified by a large amount of water,washed by the methanol, and is dried under vacuum, thereby forming thePmIA prepolymer.
 13. The method in accordance with claim 10, wherein thenylon-6 prepolymer is made by the steps of: the diamine type nylon-6 orhigh molecular weight nylon-6 and the coupling agent are reacted andpolymerized with the p-aminophenyl acetic acid (P-APA).
 14. The methodin accordance with claim 13, wherein in preparation of the diamine typenylon-6, nine ε-caprolactam and one ε-aminohexanoic acid in the nitrogensystem are reacted during a period of time at the temperature of 150°C., then increased to the temperature of 180° C. to continue to reactduring a proper period of time, and then successively increased to thetemperature of 200° C., then an excessive hex-amethylene diamine (HMDA)is dipped into the system and is reacted during a period of time, thenthe system is increased to the temperature of 250° C. to continue toreact during a period of time, then reduced to the room temperature,then mixed with water to be cured, then circulated during 24 hours withthe rate of the water and methanol equal to 4:1, and is dried undervacuum, thereby making the diamine type nylon-6.
 15. The method inaccordance with claim 13, wherein in preparation of the high molecularweight nylon-6, nine ε-caprolactam and one ε-aminohexanoic acid in thenitrogen system are reacted during 2 hours at the temperature of 150°C., then increased to the temperature of 250° C. to continue to reactduring 4 hours, then reduced to the room temperature, then mixed withwater to be cured, then dried under vacuum, then dissolved by the formicacid, then cured by a large amount of water, then washed by themethanol, and then dried under vacuum, thereby making the high molecularweight nylon-6.
 16. A method for manufacturing a molecular composite ofan industrial nylon, in preparation of the polyblend, the finishednylon-6 and the PmIA are dissolved in the formic acid to form an uniformstate, then deposited and cured by a large amount of water, thenstationarily placed for a few days, then washed by the methanol, andthen dried in a vacuum manner, thereby forming the polyblend.
 17. Themethod in accordance with claim 16, wherein the nylon-6 is replaced bythe nylon-66.
 18. The method in accordance with claim 16, wherein thepolyblend can be heat pressed by a heat forming press under the pressureof 20 kg/cm² and the temperature of 230° C. during 20 minutes, and isnaturally cooled to the temperature of 60° C., thereby forming a sheetplate.